1. Field of the Invention
The present invention is directed to a latch apparatus, and in particular to a latch with a locking live bolt that is locked in an extended position by a movable slide positioned behind the extended live bolt in the latch housing.
2. Related Art
Lockable live bolts are well known and have been used for many years. Typically, the locking mechanism that locks the live bolt is housed away from the live bolt, such as a handle that actuates the live bolt. The live bolt hub is typically mounted in the apparatus housing at a position below the live bolt, and the dead bolt is generally mounted at a position below the live bolt and the live bolt hub. A dead bolt cam actuates the dead bolt and is typically mounted in the housing below the dead bolt.
This configuration of latch apparatus components requires a relatively long apparatus housing in order to align all of the components for proper actuation of the live bolt and dead bolt while maintaining a specified depth that the apparatus extends into the door. A longer apparatus housing requires additional housing materials and support features as compared to a latch apparatus without one of the above-mentioned components.
The need for aligning the latch apparatus components in this particular order has, over time, helped to establish a loosely followed industry standard for the placement of live bolt handles and dead bolts relative to the position of the live bolt in the apparatus housing. However, in certain applications, it may be advantageous to provide a dead bolt and its actuating members or a live bolt actuating handle in the apparatus housing above the live bolt, whereas prior art latches do not provide such an option.
An additional drawback of prior art latches is the ease in which a live bolt can be retracted without actuating the live bolt handle. For example, in some configurations where the door to which the apparatus is mounted is “locked” only by locking the live bolt handle (not by locking the live bolt itself or a dead bolt), the live bolt may be forced into a retracted position by pushing inward on the extended end of the live bolt. The live bolt is retractable in this scenario even though the handle is locked. Such a method may be used by a person opening a “locked” door when they do not have access to the live bolt handle or a key to unlock the live bolt handle. A latch apparatus addressing these and other known disadvantages would be an important advance in the art.